The idea of converting the energy of hydrometeors into electricity perhaps goes back to the early work of Madden et al. (1998)1 and Förster et al. (2004)2. It was for the purpose of measuring the kinetic energy of raindrops with the use of piezoelectric device. A more perspective work was performed by Salmi and Ikonen (2005)6 with the use of “The Vaisala RAINCAP sensor”. The work was aimed on acoustic detection of individual raindrop impacts. However, Jean-Jacques Chaillout et al. (2008)3 from France's Atomic Energy Commission (CEA) in Grenoble had claimed the first whom recognized the importance of converting the impact energy of raindrops into electricity.
Obviously, the work of Jean-Jacques Chaillout and his colleagues dealt with the conversion of the impact energy of “rain drops” with the use of piezoelectric materials under controlled conditions (indoor).